DebugFn                 Capture arguments of exception throwing
                        function call for later debugging.
DebugFnE                Capture arguments and environment of exception
                        throwing function call for later debugging.
DebugFnW                Wrap a function for debugging.
DebugFnWE               Wrap function to capture arguments and
                        environment of exception throwing function call
                        for later debugging.
DebugPrintFn            Capture arguments of exception throwing
                        function call for later debugging.
DebugPrintFnE           Capture arguments and environment of exception
                        throwing function call for later debugging.
ateval                  Evaluate an expression with '@name'
                        substitution.
beval                   Evaluate an expression with '(!!name)'
                        substitution.
buildNameCallback       Build a custom writeback function that writes
                        state into a user named variable.
let                     Execute expr with name substitutions specified
                        in alias.
letprep                 Substitute text.
restrictToNameAssignments
                        Restrict an alias mapping list to things that
                        look like name assignments
wrapr                   'wrapr': Wrap R Functions for Debugging and
                        Ease of Use
